Dredger



H. HOHMAN.

DBEDGER.

APPLICATION FILED JAN. I9, I920- Y, Patented Oct. 26,1920.

INVEN TOR.

; .HENRY HOHMAN, OF STOCKTON, CALIFORNIA; I

DREDGER.

T0 allwhomz'tmay concern. v I

Be it known that I, HENRY HOHMAN, a citizen of the United States,residing at Stockton, in the county of San Joaquin, State of California,have invented certain new and useful Improvements in'Dredger's; and I dodeclare the following to be a full,

clear, and exact description of the same, refchain and bucket type usedfor mining and channel dredging purposes.

The principal object of the invention is to so arrange the chain andbuckets that the bank from which the dirt is being removed will be freefrom the tendency to cave in which is a common source of annoyance withthe use of the ordinary bucket .dredger, which digs entirely under waterand undermines the bank.

Another object is to position the bucket mechanism relative to the hullof the dredger so that the latter will always remain substantially on aneven keel. I

A third object is to run the chain onball bearingsat that part havingthe working strain and Weight thereon, these balls being so mounted thatthere is very little likelihood of their sticking or otherwise refusingto function under working conditions and with which the chain will besubject to very little frictional wear.

A further object of the invention is.to produce a simple and inexpensivedevice, and yet one which will be exceedingly effectiveg'for. thepurposes for which it. is designed. These objects I accomplish by meansof such structure and relative arrangement of parts as. willfullyqappearby a perusalof the following specification and claims.

Inthe draw ngs similar characters of reference ind1cate correspondingparts 1n the several views. V V

Figure 1 1s a s1deelevat1on of the dredger,

the hull being partly broken off at one end. Fig. 2 is an enlargedfragmentary longitudinal section showing the chain sup-- porting ballarrangement.

Fig; 3 is an enlarged fragmentary cross section taken on a line 33 ofFig. 1.

Referring now more particularly to the Specification of Letters ra$nt.-.t t d t 2 1 2 Application filed January 19', 1920. Serial No. 352,312.

keelor under side at one end forms an, ene larged circle as at 2depending for some distance below the normal keel level 1 and" alsoprojecting above the water level for a considerable distance, as at 3. 1

This circular portion is so designed relative to the hull that thecenter of radius ofcurvature is somedistance above the water l1n.e,"asatA. I V V Transversely spaced channels 4 are secured around this circularportlon and eX- tend up therebeyond at the outer or high end'at atangential angle thereto to a point a suitable distance above the hull,terminating adjacent polygonal sidedtumblers 5 mounted in a supportingframework 6 earj The tumblers are in vertical alinement.

ried by the hull.

characters of reference on the drawings, the V we numeral 1 denotes afioatable hull whose with the channels 4:, and are driven by anysuitable means such as a chain drive 7 from a power plant carried bythehull inside the deck house 8. V g V Over the tumblers and around thechannels afrun endless'chains '9, each link of which has a length'equalto the length of one side of the tumblers. This construction, as willbeevident permits the chains to be positively driven, and does away withthe usual sprocket wheel and its attendant frictional wearingcontact'with the chain, It

also enables me to use plain pieces of metal for the links,;instead ofhollow ordouble members .with rollers, eto., to engage the sprockets,which-are subject to rapid wear under the abrasive effects ofdirt andgrit. These chains run in the channels 4 and;

ried in the channels between thebottom of; the same and the under sidesof the chains are guided by the sides thereof; while carare'balls 10,adapted for limited rolling by the hull and sloping downwardlyi fromvthe opposite side of the tumblers 5.: v

; movement longitudinally of the channels,

being held in such limits by stops 11' secured to or bent up fromthebottom of the chanweight of the load dug is carried by the balls 10. 7

When a link having a loaded bucket there on is passing over the balls,the latter roll in the channel to the upper stop .11 therefor. When alight or idle link passes thereby, the strain is removed from the ball,and a the latter then works back to its normal pocontact,

sition against its lower stop, ready for the next loaded link.

The balls havingconsiderable freedom of movement, precludes thepossibility of any of them becoming clogged and inactive, and insuresthat the chain will always have a comparatively frictionless rollingcontact therewith rather than a sliding or rubbing thus insuringlongevity of the parts. V

The relatively great diameter of the portion 2 insures that the bankfrom which the material is being. dug will retain a gentle curvature ofprofile, not apt to cave in.

From the foregoing description it will be readily seen that I haveproduced such a de-.

vice as substantially fulfils the object of the invention as set forthherein.

WVhile this specification set forth in detail the present and preferredconstruction of the device still in practice such deviations from suchdetail may be resorted to as do not form a departure from the spirit ofthe invention, as defined by the appended claims.

Having thus described my invention, what I claim as new and useful anddesire to secure by Letters Patent is l. A dredger including a waterborne hull, a circular portion forming one end thereof extending belowthe normal keel level of the hull and above the water line,

. and endless bucket-carrying chains passing around such circularportion.

2. A dredger including a'water bornehull, a circular portion on one endthereof extending below the normal keel level of the hull and above thewater line, the center of such portion being above the water line,

transversely spaced channels around" such "circular portion, endlessbucket-carrying chains guided in such channels, and balls in thechannels bearing against the inner face of the chains, the balls beingadapted for lninted longitudinal movement in the channe S. r

3. A dredger including a water borne hull, a clrcular portion on one endthereof ex- .tending below the normal keel level of the hull and abovethe water line, the center I of such portlon being above the water line,

transversely spaced channels. around such circular portlon, endlesschalnsgulded in the channels, buckets on thealternate ones of' the lmksof the chains, balls in such channels bearing against the inner surfaceof the chains and stops in the channels between each ball, the latterhaving longitudinal freedom of movement between the stops.

4. A dredger including a water borne hull, a circular portion formingone end thereof extending below the normal keel-level of the hull andabove the waterline, the center of such portion being above the waterline, transversely spaced channels around such circular portion, andendless digger carrying chains guided in such channels.

5. A dredger including a water borne hull, a circular portion formingone end thereof extending below the normal keel-level ofthe hull andabove the water line, the center of such portion being above the waterline, transversely spaced channels around such circular portion, endlessdigger carrying chains guided in such channels, and means in thechannels for reducing the friction of contact of the chains therewith.

6.. A dredger comprising a water-borne hull, endless digger-carryingchains, and guides for .said chains projectingdownwardly beyond one endof the hull, such guides being substantially circular, and projectingbelow the normal keel-level of the hull and to a point above the waterline.

7. A dredger comprising a waterborne hull, endless digger-carryingchains, and guides for said chains projecting downwardly beyond one endof the hull,--such guides being substantially circular, and projectingbelow the normal keel-level of thelowest point of the chains to thetopof the guides above the water line.

In testimony whereof I aflix m si nature.

HENRYH H' AN,

